This tool is complete crap. The locking ring broke in half by simply wiggling the wheel with your hand to see how much play there was between the wheel and the bottom bracket. Both the tool and the knurling wheels scratch very easily and the wheels don't appear to be heavily hardened as they are very easily damaged. I know this because when releasing the locking clip from the axle pin the wheel fell onto the table top of my welding table and the edge of the wheel was slightly deformed. Pure Chinese junk. If you plan on using this tool in any capacity other than seeing it in your desk drawer, I recommend you put your money elsewhere.